The New World Atlas of Artificial Sky Brightness
30.06.2016

How far are you from a naturally dark night sky? In increasing steps, this world map (medium | large) shows the effect of artificial night sky brightness on the visual appearance of the night sky. The brightness was modeled using high resolution satellite data and fit to thousands of night sky brightness measurements in recent work.

M42: The Great Orion Nebula
29.11.2017

Few astronomical sights excite the imagination like the nearby stellar nursery known as the Orion Nebula. The Nebula's glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud.

Cygnus Without Stars
30.11.2020

The sky is filled with faintly glowing gas, though it can take a sensitive camera and telescope to see it. For example, this twelve-degree-wide view of the northern part of the constellation Cygnus reveals a complex array of cosmic clouds of gas along the plane of our Milky Way galaxy.

At The Core Of M15
17.01.1998

Densely packed stars in the core of the globular cluster M15 are shown in this Hubble Space Telescope (HST) image. The star colors roughly indicate their temperatures - hot stars appear blue, cooler stars look reddish-orange.

GRB970508 Delivers Predicted Radio Emission
21.05.1997

New evidence bolsters once controversial claims that Gamma-Ray Bursts (GRBs) are the most powerful explosions ever found by humanity. Two weeks ago, an average GRB became instantly historic when prompt, coincident X-ray and optical emissions were identified.

SN1987A s Cosmic Pearls
20.02.2004

In February 1987, light from the brightest stellar explosion seen in modern times reached Earth -- supernova SN1987A. This Hubble Space Telescope image from the sharp Advanced Camera for Surveys taken in November 2003 shows the explosion site over 16 years later.

A Beautiful Trifid
30.05.2009

The beautiful Trifid Nebula is a colorful study in cosmic contrasts. Also known as M20, it lies about 5,000 light-years away toward the nebula rich constellation Sagittarius. A star forming region...

Four Lasers over Mauna Kea
23.06.2014

Are lasers from giant telescopes being used to attack the Galactic center? No. Lasers shot from telescopes are now commonly used to help increase the accuracy of astronomical observations. In some sky locations, Earth...

The Light, Dark, and Dusty Trifid
10.08.2024

Messier 20, popularly known as the Trifid Nebula, lies about 5,000 light-years away toward the nebula rich constellation Sagittarius. A star forming region in the plane of our galaxy, the Trifid does illustrate...

X Ray Moon
2.09.2000

This x-ray image of the Moon was made by the orbiting ROSAT (Röntgensatellit) Observatory in 1990. In this digital picture, pixel brightness corresponds to x-ray intensity. Consider the image in three parts: the bright hemisphere of the x-ray moon, the darker half of the moon, and the x-ray sky background.